Story – Matt Worden – WSJ.comQtrax, a free, ad-supported and legal music downloading service, was launched in the U.S. Thursday with access to music from all four major record labels and a number of independents.

The launch comes as ad-supported online media businesses are struggling amid the global economic downturn and the vast array of cheap ad inventory that pervades the Web. Many media moguls are revisiting subscription models to regain financial stability.

But the proliferation of illegal online music-sharing sites suggests that consumers have an appetite for free song downloads. Qtrax is wagering it can bring legitimacy to the practice and build a mass media outlet over time despite a number of technical drawbacks to its service.

“Our philosophy is to work with as many people as possible that are exploring new models for connecting consumers with our content in a legal way,” said Jeanne Meyer, a spokeswoman with EMI Music.

Qtrax, a subsidiary of Brilliant Technologies Corp. (BLLN), requires consumers to download a Mozilla browser-based application that serves as a music player and Web browser with display ads served by online ad networks. Free downloads are then made available that include digital rights management software, limiting the user’s ability to share the files and use them on other music players.

The service currently isn’t available on Apple Inc. (AAPL) computers, and the files cannot be played on iPods, though Allan Klepfisz, president and chief executive of Qtrax, said these obstacles can be overcome soon. The service can be used on a number of Windows-enabled high-end mobile devices and MP3 players. Continue Reading